Day: December 3, 2020

113100-53-1, A common heterocyclic compound, 113100-53-1, name is 1-Methyl-3-(trifluoromethyl)-1H-pyrazole-4-carboxylic acid, molecular formula is C6H5F3N2O2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

General procedure: Pyrazole acid chlorides 6a-b were prepared by refluxing 4a-b in thionyl chloride for 8 h. Pyrazole acid chlorides 6a-b (12 mmol) in anhydrous tetrahydrofuran (THF; 30 mL) were slowly added to a solution of amine derivatives or 5-methylisoxazol-3-ol (10 mmol) and K2CO3 (1.38 g, 10 mmol) in anhydrous THF (30 mL) at a controlled temperature of 5 C. The reaction proceeded at room temperature until 6a-b was no longer tested by TLC. The reaction solution was then filtered and the solvent distilled. The residue was dissolved in ethyl acetate, washed with water and brine, dried over anhydrous sodium sulfate and recrystallized to generate the target pyrazole carboxamides and isoxazolol pyrazole carboxylates (7aa-bk). The product yields ranged from 40% to 80%. All 20 compounds were novel, and the physical and spectral data for these compounds are listed below.

The synthetic route of 113100-53-1 has been constantly updated, and we look forward to future research findings.

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 5334-40-7, name is 4-Nitro-1H-pyrazole-3-carboxylic acid, A new synthetic method of this compound is introduced below., 5334-40-7

In a 250 mL round bottom flask, 7.0 g (36.6 mmol) of crude I-f was added. 4-nitro-1H-pyrazole-3-carboxylic acid 6.3 g (40.1 mmol), EDC¡¤HCl 8.4 g (44.0 mmol), HOBt 6.0g (44.4mmol) and anhydrous DMF 100mL, Stir at room temperature for 24 h. The disappearance of the starting material by TLC (methanol: chloroform = 1:10). The reaction solution was poured into 200 mL of ice water to precipitate a large amount of pale yellow solid, which was allowed to stand, and a yellow solid was obtained. The obtained crude product was recrystallized from a mixed solvent of ethyl acetate and methanol to give (I-g) 8.6 g (yield: 71.0%).

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Adding some certain compound to certain chemical reactions, such as: 2458-26-6, name is 3-Phenyl-1H-pyrazole, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 2458-26-6. 2458-26-6

Teri-butyl (R )-(2-(3-phenyl-1H-pyrazol- 1 -yl)propyl)carbamate 3-Phenyl-1 H-pyrazole (250 mg, 1 .73 mmol), cesium carbonate (5.65 g, 17.30 mmol) and (S)-1 -((ieri-butoxycarbonyl)amino)propan-2-yl methanesulfonate (876 mg, 3.46 mmol) were combined in anhydrous N,N- dimethylformamide (10 ml). The resulting suspension was heated to 50 C and the progress of the reaction was monitored by TLC. Once the reaction was complete (~ 18 h) the reaction mixture was quenched by addition of water and the product was extracted with ethyl acetate three times. The organic layers were combined and washed with a saturated aqueous solution of sodium chloride. All of the volatiles were removed in vacuo. The crude material was purified by column chromatography, eluting 5-10% ethyl acetate/petroleum spirits to give the title compound as a colourless solid (60 mg, 12%). LRMS [M+H]+ 302.2 m/z; HRMS [M+H]+ 302.1863 m/z, found 302.1867 m/z; 1 H NMR (400 MHz, CDCI3) delta 7.85 – 7.72 (m, 2H), 7.41 – 7.33 (m, 3H), 7.31 – 7.25 (m, 1 H), 6.54 (d, J = 2.3 Hz, 1 H), 5.05 (d, J = 1 .1 Hz, 1 H), 4.26 (dd, J = 13.8, 4.5 Hz, 1 H), 4.21 – 4.10 (m, 1 H), 4.05 (dd, J= 12.6, 6.7 Hz, 1 H), 1 .41 (s, 9H), 1 .12 (d, J = 6.8 Hz, 3H).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 3-Phenyl-1H-pyrazole.

176969-34-9, Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 176969-34-9, name is 3-(Difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid, A new synthetic method of this compound is introduced below.

The pyrazole acid chloride is prepared from 3- difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid and thionyl chloride in heptane shortly before use. In a 500-mL round-bottomed flask provided with alkaline scrubber, pyrazole acid (74.0 grams, 0.42 mol) is suspended in heptane (170 mL) . Dimethylformamide (0.70 grams, 0.009 mol) and thionyl chloride (55.0 grams, 0.462 mol) are added and the bi-phasic mixture is stirred and heated at 42-45 C.After complete conversion of pyrazole acid (2.5 hours), the solvent and excess thionyl chloride are completely removed by vacuum distillation.Liquid pyrazole acid chloride is obtained as the residue (approximately 81.0 grams)

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

The chemical industry reduces the impact on the environment during synthesis 4522-35-4, name is 3-Iodo-1H-pyrazole, I believe this compound will play a more active role in future production and life. 4522-35-4

Step 2: 3-iodo-l-methyl-lH-rhoyrazole.To a stirred solution of 3-iodo-leta-rhoyrazole (0.5 g, 2.6 mMol) in anhydrous DMF (5.0 mL) was added iodor¡ãethane (3.7 g, 25.8 mMol). The resulting solution was cooled to 00C, and NaH (0.11 g, 2.8 EPO mMol, 60% dispersion in mineral oil) was added. The reaction mixture was allowed to warm to ambient temperature, and was stirred for 15 minutes. Water (20 mL) was added, and the resulting solution was extracted with EtOAc (1 x 30 mL). The organic layer was washed with water (2 x 30 mL), and brine (1 x 30 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to afford the title compound. LRMS (ESI) calculated for C4H5IN2 [M+H]+, 208.9; found 209.0.

The chemical industry reduces the impact on the environment during synthesis 4522-35-4. I believe this compound will play a more active role in future production and life.

5932-27-4, A common compound: 5932-27-4, name is Ethyl 1H-pyrazole-3-carboxylate, belongs to pyrazoles-derivatives compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

Sodium hydride (60 wt % in mineral oil; 3.14 g, 78.5 mmol) was added to a solution of ethyl 1H-pyrazole-3-carboxylate (10 g, 71.4 mmol), benzyl bromide (12.7 mL, 107 mmol), and DMF (100 mL) at 0 C. portionwise over 3 min with vigorous stirring. The mixture was allowed to warm to r.t. over 18 h and then diluted with ethyl acetate. The resulting mixture was washed with water (¡Á3) and saturated aqueous sodium chloride. The organic layer was then dried over sodium sulfate, filtered and concentrated under reduced pressure. The resulting residue was purified by flash column chromatography, elution gradient 0 to 50% ethyl acetate in hexanes, to afford ethyl 1-benzyl-1H-pyrazole-3-carboxylate (11.3 g, 69%) as a slower eluting amber oil. Also isolated was ethyl 1-benzyl-1H-pyrazole-5-carboxylate (2.69 g, 16.4%) as a light amber oil. (1276) Ethyl 1-benzyl-1H-pyrazole-3-carboxylate: (1277) 1H NMR (DMSO-d6 27 C.) 1.28 (3H, t), 4.25 (2H, q), 5.43 (2H, s), 6.77 (1H, d), 7.23-7.42 (5H, m), 7.97 (1H, d). m/z: ES+[M+H]+ 231.

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Ethyl 1H-pyrazole-3-carboxylate, other downstream synthetic routes, hurry up and to see.

3469-69-0, Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 3469-69-0, name is 4-Iodopyrazole, A new synthetic method of this compound is introduced below.

ieri-Butyl 4-iodo-1 H-pyrazole-1 -carboxylate (2); [00189] 4-lodopyrazole (1) (7.85g 40.4mmole) was dissolved in THF (120ml_) and triethylamine (8.5ml_, 6.12g 60.5mmole) and di-terf-butyl dicarbonate (9.7g, 44.5mmole) were added. The reaction was stirred at r.t. for 3 hours. The THF was evaporated and ethyl acetate (100ml_) was added. The solution was washed with water (2x50ml_) and with brine, then dried and evaporated to leave an oil (14.2g). The crude product was purified by chromatography on a pad of silica in a sinter (10cm diam, 6cm thick) eluted with 10% ethyl acetate in cyclohexane (1 1 x90ml_), then 20% ethyl acetate in cyclohexane (3x90ml_) to give the protected pyrazole 2 (1 1 .66g 98%). 1H-NMR (CDCI3, 500MHz): delta 1 .68 (s, 9H), 7.73 (s, 1 H), 8.17 (s, 1 H).

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

These common heterocyclic compound, 5932-27-4, name is Ethyl 1H-pyrazole-3-carboxylate, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 5932-27-4

(b) 4-Fluoropyrazole-3-carboxylic acidSodium hydroxide (aq., 2M, 18 mmol; 9 mL) was added to a solution of a mixture (-2:1) of 4-fluoropyrazole-3-carboxylic acid ethyl ester and pyrazole-3-carboxylic acid ethyl ester (1.2 g, ~8 mmol; see step (a) above) in dioxane (9 mL) at rt and was stirred for 16 h. A second portion of aqueous sodium hydroxide (2M, 18 mmol, 9 mL) was added and the mixture was stirred for another 4 h. The mixture was acidified with HCl (aq., 2M, 20 mL), concentrated, stirred with MeOH (30 mL) and filtered. The filtrate was concentrated and the residue crystallised from HCl (aq., 0.01M)

Adding some certain compound to certain chemical reactions, such as: 5334-40-7, name is 4-Nitro-1H-pyrazole-3-carboxylic acid, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 5334-40-7. 5334-40-7

4-Nitropyrazole-3-carboxylic acid (2.5 g; 15.9 mmol) was added to a stirred solution of aniline (1.6 ml; 17.5 mmol), EDC (3.7 g; 19.1 mmol), and HOBt (2.6 g; 19.1 mmol) in N,N-dimethylformamide (DMF) (25 ml), then stirred at room temperature overnight. The solvent was removed by evaporation under reduced pressure and the residue triturated with ethyl acetate / saturated NaHCpsi3 solution. The resultant solid was collected by filtration, washed with water and diethyl ether then dried under vacuum to give 2.85 g of the title compound (sodium salt) as a yellow / brown solid. (LC/MS: Rt 2.78, [M+H]+ 232.95).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 4-Nitro-1H-pyrazole-3-carboxylic acid.

The chemical industry reduces the impact on the environment during synthesis 14521-80-3, name is 3-Bromo-1H-pyrazole, I believe this compound will play a more active role in future production and life. 14521-80-3

Step 1: 1-(2-(4-bromo-1H-pyrazol-1-yl)ethyl)pyrrolidin-2-one (162) To a solution of 3-bromopyrazole (5 g, 34 mmol), 1-(2-hydroxyethyl)pyrrolidin-2-one (5.75 g, 51 mmol), PPh3 (13.38 g, 51 mmol) in THF (100 mL) was added DEAD (8.89 g, 51 mmol) and the reaction mixture was stirred at RT overnight. The mixture was concentrated, co-evaporated with Et2O then dissolved in Et2O and cooled in a fridge for 3 hrs whereupon Ph3P=O precipitated out. The mixture was then filtered and concentrated to afford title compound 162 (8.78 g, 100% yield) which was used in the next step with no additional purification. MS (m/z) 259.12/261.12 (M+H).

The chemical industry reduces the impact on the environment during synthesis 14521-80-3. I believe this compound will play a more active role in future production and life.